Field of the Invention
The present invention relates to an electromagnetic wave shielding support base-attached encapsulant, an encapsulated substrate having semiconductor devices mounted thereon and an encapsulated wafer having semiconductor devices formed thereon each using the encapsulant, and a semiconductor apparatus manufactured from these.
Description of the Related Art
With remarkable progress of digital technology, miniaturization and higher performance of electronic devices represented by personal computers and mobile phones have been required. For example, a printed wiring substrate, which is a representative part of these devices, has been improved toward high density mounting and miniaturization. Along with this current, an electronic device having highly integrated semiconductor parts is formed with a circuit that tends to sensitively respond to outside noise and cause malfunctions or failures. In addition, this device emits an unintended high-frequency energy outside.
As the electromagnetic wave shield that focuses on the prevention of electromagnetic noise emission to the outside of electronic/electric devices and electromagnetic noise entrance from the outside, reflective shielding materials have been conventionally used in many cases.
Accordingly, at first, electronic/electric devices had been shielded from electromagnetic noise by coating the whole housing with a conductive material or using a metal or metallic mesh cover (Patent Documents 1 to 3). After that, electromagnetic wave shielding is becoming to be applied to individual semiconductor packages. However, if the sizes of parts within the package are uneven, the sheet metal shield becomes tall because of coating the whole housing with a conductive material or using a metal or metallic mesh cover, which causes problems of occurrence of dead space and unachievable film-thinning due to the accumulation of heat, etc.
Besides, although electromagnetic wave shielding properties have been conventionally applied to individual packages, it is now required to provide electromagnetic wave shielding properties at the time of encapsulating a large-diameter wafer or a large-area substrate such as inorganic, organic, or metal substrate, in view of versatility, economical efficiency, and mass-productivity.
When a large-area substrate or a large-diameter wafer of 300 mm (12 inches) or more is encapsulated, there is a problem that the substrate or the wafer occasionally warps due to shrinkage stress of the epoxy resin or the like at the time of encapsulating and curing, and especially, the large-diameter wafer with thin thickness is liable to warp. In addition, when a semiconductor-device mounting surface of a large-area substrate having semiconductor devices mounted thereon is encapsulated, a problem arises that the semiconductor devices are peeled from the substrate by shrinkage stress of the epoxy resin or the like at the time of encapsulating and curing. Accordingly, there is a big problem that encapsulated large-area substrates and large-diameter wafers cannot be used for mass-production. Therefore, there is an attempt to encapsulate a large-diameter wafer or a large-area substrate such as organic, inorganic, or metal substrate by using a substrate-attached encapsulant in which a resin layer for use in encapsulating is formed on a substrate (Patent Documents 4 and 5).
In particular, there has been demanded a support base-attached encapsulant that can collectively encapsulate a semiconductor-device mounting surface of a substrate having the semiconductor devices mounted thereon or a semiconductor-device forming surface of a wafer having semiconductor devices formed thereon without occurrence of warping of the substrate or the wafer, peeling of the semiconductor devices from the substrate, and breakage of the wafer even in the case that thin semiconductor devices are encapsulated, and that has excellent electromagnetic wave shielding property, reliability such as heat resistance and moisture resistance after encapsulating, and extremely high versatility.